ii6 



MORPHOLOGY 



jam, jamrul, deshi-badam (Country Almond),. &c., 

 are usually wind-pollinated, though insect-pollination 

 is by no means uncommon. 



In entomophilous or insect-flowers the pollen-grains 

 are larger, more or less sticky, and their exterior is 

 often studded with spines, knobs, or other projections 

 which facilitate their adhesion to the body of an 

 insect. At times the pollen-grains are bound together 

 in masses by threads of a delicate sticky substance, 

 so that their transport by wind 

 is rendered impossible. Insect- 

 flowers employ many means of 

 attraction for enticing suitable 

 insects to visit them, such as 

 colour, odour, proffer of food in 

 the form of pollen-grain or nectar 

 or enclosed sap. It is the petals 

 or perianth -leaves that, owing 

 to their bright colour, play the 

 leading part in making the 

 flowers 

 visitors, 

 petals is often discriminative, 

 corolla is not visible to insects on the wing, it is less 

 brightly coloured than the side which they are able 

 to see. The perianth-leaves, which spread out like a 

 star in the sunlight, are of a shining colour on their 

 inner face, while on the outer or under surface they 

 are either green or of a dull colour. In shalook 

 {Nymphcea alba) (fig. 104), for instance, the inner face 

 of the sepals visible to insects on the wing is coloured 

 white, while the outer or under face, which lies upon 

 the water and is therefore not visible from above, has 

 a green colour. In urceolate and campanulate flowers 

 the inner surface is less conspicuous tharj the outer 



104. — Flower of Shalook 

 {^Nymphfea alba) 



conspicuous to insect 

 The coloi-ation of the 

 Thus, if one side of a 



